that the block would have to be demolished to make way for crossrail as it's planned to pass directly under and have a stop/interchange at Tottenham Court Road Station. but that's currently in development limbo as best I'm aware as the Government won't stump up the cash.

Anyway, I don't think even Westminster Council would be soulless enough to greenlight a huge tesco on the corner of Oxford street and Charing Cross Road. the Soho residents associations and various community groups would go bananas, for a start.